Discussion of public health and health care policy, from a public health perspective. The U.S. spends more on medical services than any other country, but we get less for it. Major reasons include lack of universal access, unequal treatment, and underinvestment in public health and social welfare. We will critically examine the economics, politics and sociology of health and illness in the U.S. and the world.

Wednesday, September 21, 2005

Another open door crashed through . . .

Believe it or not (and I know this will seem incredible), kids who watch a lot of TV tend to get fat. According to a new study from New Zealand in the International Journal of Obesity, which followed kids from birth through age 15, "BMI and prevalence of overweight at all ages were significantly associated with mean hours of television viewing reported in the assessments up to that age. These associations were stronger in girls than boys. The associations remained significant after adjusting for parental body mass indices and socio-economic status." The investigators say the effect size is small, but actually larger than those commonly reported for nutritional intake and physical activity.

Meanwhile, there has been controversy about whether TV also makes kids stupid, or more accurately, educational underachievers. The difficulty is in deciding whether kids who just aren't interested in school work to begin with watch more TV, or whether TV watching in fact makes them do poorly in school. And maybe "educational TV" is good for your brain, who knows?

What appears to have been the same cohort was also assessed up to 26 years of age for dropping out of high school and getting a college degree. According to a report in the Archives of Pediatric and Adolescent Medicine (subscription only, sorry):

The mean time spent watching television during childhood and adolescence was significantly associated with leaving school without qualifications and negatively associated with attaining a university degree. Risk ratios for each hour of television viewing per weeknight, adjusted for IQ and sex, were 1.43 (95% confidence interval [CI], 1.24–1.65) and 0.75 (95% CI, 0.67–0.85), respectively (both, P

These are very strong effects -- and note that they control for IQ. Here's a picture:

Note that about 40% of the kids who watched less than an hour of TV per weeknight graduated from college, while 10% of kids who watched 3 hours or more did so.

So now you know how to make your kids fat and stupid. Glad I could help.

Apologies: I forgot to give the reference to the article. Hancox et al. Association of Television Viewing During Childhood With Poor Educational AchievementArch Pediatr Adolesc Med.2005; 159: 614-618.